Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4644f00309c1fcd…

MALICIOUS

PDF

84.8 KB Created: 2021-09-16 13:51:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: eaa7adcffa525d3a9c1e7c07d27eb0e6 SHA-1: 10754a1cdc5242c369c244f058c731fe7b5d4f00 SHA-256: f4644f00309c1fcdc8bd00a2e1d68fbcc01cc8d7be9e4f6b8f356dd7d955b8c9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external links, including one pointing to a compromised WordPress upload, suggesting it functions as a link farm or phishing lure. The presence of embedded URLs and the PDF structure further support its role in directing users to potentially harmful external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://huntic.ru/uplcv?utm_term=mettere+suoneria+su+android
    • http://damosushipleasanthill.com/uploads/files/serowemasiripok.pdf
    • http://tecsun-moscow.ru/docs/file/42590189085.pdf
    • http://interel-rus.ru/test/sites/default/files/file/75564947741.pdf
    • http://jrecchina.com/ckeditor/ckfinder/userfiles/files/10061830320.pdf
    • http://mya1fc.com/files/ckuploads/files/lamenugik.pdf
    • http://stellarp.com/userfiles/file/pukumopuzowepovubami.pdf
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e9955e02ba---75211731354.pdf
    • https://togeltop.net/contents/files/69347006961.pdf
    • http://rockbond-aac.com/id-admin/fckImages/file/gidoxura.pdf
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/e1ce29166b8546386faa1e70862ede34/ninugigu.pdf
    • http://jca-t.com/fck_image/file/pafore.pdf
    • http://liavanhaeringen.nl/userfiles/files/vemuxajerobojir.pdf
    • http://shijijiaming.net/filespath/files/20210913043609.pdf
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16142719946669---teguxagave.pdf
    • http://studiocastigli.eu/userfiles/files/89654298746.pdf
    • https://carcarnet.com/home/sandbox/domains/hkdance.tritek.hk/public_html/ckfinder/userfiles/files/26308101602.pdf
    • http://tokstar.com/_UploadFile/Images/file/zibujulofileseteros.pdf
    • https://mlspoland.co/files/file/4047425840.pdf
    • https://dalyanestate.com/userfiles/file/44791337336.pdf
    • https://clickbox.ro/images/file/vesikevadiwodekutev.pdf
    • http://emekyesiltepe.net/images_upload/files/sikogujefazukidesufuv.pdf
    • http://land89.com/ckupload/files/55848430365.pdf
    • http://budropol.de/Upload/file/liwozi.pdf
    • https://mr-alian.com/upload/ckfinder/files/nedivoporutirumeravik.pdf
    • http://anapharmata.hu/ckfinder/core/connector/php/files/wukajogonibomu.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e6ff.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6FF 16792 bytes
font_01_sfnt_off0000ff16.bin
a692d3edec9aae124876e0772ec14d3db4b7b66002031e27e2efbb2899a44ed6
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF16 10288 bytes
font_02_sfnt_off00011662.bin
4283c0f9e2796537f072597d6378a663256f910a328e37f2d5ac1b6027bb7f11
pdf-font-stream PDF embedded font (sfnt) at offset 0x11662 18064 bytes